Numerical simulation of magnetic bead chains in a magnetic field using 3-D distinct element method

Abstract

Formation of magnetic bead chains in a magnetic field was numerically simulated with the Distinct Element Method in order to apply for improvements of a magnetic brush development system in electrophotography. Simulated chain configurations, length and slant angle, and dynamic chain forming process were compared to the experimental results. The 2-D calculation could not simulate quantitatively well the chain configurations and the process, because the magnetic interaction between beads was under estimated due to the neglect of the interaction force between three-dimensionally distributed beads. On the other hand, 3-D calculation showed good agreement with experiments and it is concluded that 3-D calculation is indispensable for the quantitative evaluation. It was also confirmed that chain configurations were determined approximately to minimize its total potential energy given by the sum of magnetic energy and gravitational energy.